1. Technical Field
The invention relates to shell structures for cooling towers of the type comprising a framework resting on foundations and a wall carried by the framework and defining a stack. It is particularly suitable for use in the field of atmospheric cooling towers of power plants producing electricity.
2. Prior Art
Most of the atmospheric cooling towers existing at the present time are formed by a monolithic structure of reinforced concrete whose height may exceed 180 meters, supporting a network of ducts for dispersing the water to be cooled over an exchange lattice.
However, other constructions have also been proposed. In particular, structures have been proposed comprising a framework, often of metal, and a thin wall formed by panels of different materials, such as composites formed from an organic matrix and metal or concrete reinforcements. The panels are assembled together by mechanical means such as bolts.
The reliability of such structures depends on maintaining permanent supervision and results in high maintenance costs. In addition, the construction of the structures is time consuming and repairs are delicate.
A shell structure of the above-defined type has also been proposed (French 2,222,516) in which the framework is formed by meridian elements connected to circumferential elements by assembling nodes, air tightness being provided by a veil or thin wall. This construction requires complex mounting operations and a large number of different elements and however does not make it possible to design a shell of optimum shape from the aeraulic point of view.